Maraković Jurica, Oresković Darko, Jurjević Ivana, Rados Milan, Chudy Darko, Klarica Marijan
University of Zagreb, Dubrava University Hospital, Department of Neurosurgery, Zagreb, Croatia.
Coll Antropol. 2011 Jan;35 Suppl 1:73-7.
The cerebrospinal fluid (CSF) formation rate (Vf) has been extensively studied by the ventriculocisternal perfusion, a method still regarded as the most precise one. This method as well as the equation for the calculation of the CSF formation rate (Vf) was established by Heisey et al on indicator dilution in perfusate. They assumed that the dilution of the indicator substance in perfusion is a consequence of newly formed CSF i.e. a higher CSF formation rate would result in a higher degree of dilution of the indicator substance. Therefore, such method is indirect and any mistake in the interpretation of the degree of indicator dilution would lead to questionable and often contradictory results regarding CSF formation rates. According to Heisey's equation, Vf shoud not depend on the rate of ventriculocisternal perfusion. However it has been shown that Vf is perfusion dependt value, and also that during perfusion the indicator substance is partially absorbed into surrounding tissue. It is possible that obtained Vf dependence on perfusion rate was caused by observed absorption of indicator substances. For that reason, in anaesthetised cats ventriculocisternal perfusion was performed at higher (252.0 microL/min) and at lower perfusion rate (65.5 microL/min) and Vf was calculated at both experimental and corrected (just for absorbed amount) values of indicator substance. Since (inspite of the correction) the difference of 12.4 microL/min between lower (15.0 microL/min) and higher perfusion rate (27.4 microL/min) was obtained, it is obvious that ventriculocisternal perfusion method cannot be considered reliable for measuring CSF formation rate.
脑脊液（CSF）生成率（Vf）已通过脑室池灌注法进行了广泛研究，该方法至今仍被视为最精确的方法。这种方法以及脑脊液生成率（Vf）的计算公式是由海西等人根据灌注液中的指示剂稀释法建立的。他们假定灌注液中指示剂物质的稀释是新生成脑脊液的结果，也就是说，脑脊液生成率越高，指示剂物质的稀释程度就越高。因此，这种方法是间接的，对指示剂稀释程度的任何错误解读都会导致关于脑脊液生成率的结果存在疑问且常常相互矛盾。根据海西的公式，Vf不应取决于脑室池灌注率。然而，已经表明Vf是一个依赖于灌注率的值，而且在灌注过程中指示剂物质会部分被周围组织吸收。所得到的Vf对灌注率的依赖性可能是由观察到的指示剂物质吸收所导致的。出于这个原因，在麻醉猫身上分别以较高（252.０微升/分钟）和较低（65.5微升/分钟）的灌注率进行脑室池灌注，并根据指示剂物质的实验值和校正值（仅针对吸收量）计算Vf。由于（尽管进行了校正）在较低（15.0微升/分钟）和较高灌注率（27.4微升/分钟）之间仍得到了12.4微升/分钟的差异，显然脑室池灌注法不能被认为是测量脑脊液生成率的可靠方法。
